1. Field of the Invention
The present disclosure relates to an optical recording and playback apparatus that records and plays back information in and from an optical recording medium such as an optical tape.
2. Description of the Related Art
An optical tape apparatus in which the recording or playback is simultaneously performed on an optical tape medium with a plurality of optical pickups by making use of an optical high-density recording technology has been proposed as a recording and playback apparatus suitable for storage application. For example, PTL 1 discloses an example of the optical tape apparatus.
Further, in an optical recording and playback apparatus, it is necessary to properly perform focus control and tracking control during recording and playback operations. Particularly, compared with the focus control, higher accuracy is required in the tracking control of the optical tape apparatus in which the optical tape is used. The tracking control, which is different from an optical disk and suitable for the optical tape, is required in the optical tape apparatus because LTM (Lateral Tape Motion) that is a vibration in a tape width direction exists up to several kHz due to running of the optical tape.
In the storage application, the optical recording and playback apparatus is expected to be used in a data center or the like in which a large amount of data is dealt, and there is a demand for performing continuous operation for a long time or maintaining stably signal quality of the recording or playback for several years. For example, PTL 2 discloses a light source unit that properly records and/or plays back information in and from the optical disk even if aging or an environmental change is generated.